Die Entdeckung der Bedeutung von Bedeutung

ZUSAMMENFASSUNG

Das Konzept der „aberranten Salienzattribution“ erklärt die Entstehung von psychotischen Symptomen der Schizophrenie damit, dass die Zuordnung von Bedeutsamkeit („Salienz“) zu Gedanken und Sinnesreizen keinen sinnvollen Regeln mehr folgt, sondern quasi chaotisch („aberrant“) ist. Unwichtige Dinge können plötzlich bedeutsam erscheinen. Wahnvorstellungen sind demnach der Versuch des Verstandes, ein kohärentes Weltbild aus Eindrücken und Gedanken zu erzeugen, deren Bedeutung stark verzerrt ist. Ein wichtiger Mechanismus dieser aberranten Salienzattribution ist eine verstärkte Signalwirkung des Botenstoffs Dopamin. In der Entwicklung der Erkrankung erzeugt eine dysregulierte Dopamin-Ausschüttung wiederholt falsche Lernsignale und somit eine „deformierte Struktur“ der Salienzattibution, die zu chronischen Wahnvorstellungen führt. Diese Theorie wurde ursprünglich von Manfred Spitzer in seiner Publikation „A computational approach to delusions“ [2] entwickelt. Sie hat weitreichende Beziehung zu Modellen von implizitem Lernen (v. a. Kurzzeithabituation, Konditionierung und Verstärkungslernen) und hat neue Perspektiven für die Therapie und die systematische Untersuchung der mechanistischen Grundlagen der Symptome der Schizophrenie eröffnet. Solche Studien haben die aberrante Salienzattribution bei Patienten – auch bereits vor Erstdiagnose der Krankheit – auf psychologischer und physiologischer Ebene nachgewiesen.

ABSTRACT

The concept of “aberrant salience attribution” explains the emergence of psychotic symptoms in schizophrenia by suggesting that the assignment of significance (“salience”) to thoughts and sensory stimuli no longer follows meaningful rules but becomes almost chaotic (“aberrant”). As a result, insignificant things can suddenly seem important. Delusions are thus seen as the mind’s attempt to create a coherent worldview from perceptions and thoughts whose importance is highly distorted. A key mechanism of aberrant salience is increased signaling of the neurotransmitter dopamine. During the development of the disorder, dysregulated dopamine release repeatedly generates false learning signals, leading to a “deformed structure” of salience attribution, which results in chronic delusions. This theory was originally proposed by Manfred Spitzer in his publication “A Computational Approach to Delusions” [2]. It has far-reaching connections to models of implicit learning (especially short-term habituation, conditioning, and reinforcement learning) and has opened new perspectives for therapy and for the systematic investigation of the pathomechanism of schizophrenic symptoms. Such studies have demonstrated aberrant salience attribution in patients — even before the first diagnosis of the illness — on both psychological and physiological levels.

Schlüsselwörter

Wahnvorstellungen - Dopamin - deformierte Struktur

Key words

Delusions - dopamine - deformed structure

Publikationsverlauf

Artikel online veröffentlicht:
10. Oktober 2024

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